I can't really say I'm disappointed because I knew what I was walking into, but I don't think I'll be playing it anymore. The funny thing is I agree with most of the positive posts in this thread but have a different takeaway.

Even though it's a 4-year old game, the combat is great and feels really good (especially if you have low ping). It's fast and combo-based and the animations are usually pretty satisfying. Like others have pointed out, the flaw is the fact that the lower your ping the more abilities you can cast. There is no GCD/limiting factor so less ping = more attacks/abilities.

Then I realized the game is really linear, you basically spawn at point A and follow the path to the end (level 45) doing the same 3 quests over and over again with different mobs. You can run pretty fast and jump really high and even glide but the world/terrain/environment is so restricting that you're limited to following an exact path most of the time. It's so restricting that there really isn't much of a point or advantage to gliding and it's actually really annoying for just traveling and getting around in general. Constantly clipping on things and having to run around a long path instead of jumping over a small hill.

Once you hit max level, the only thing left to do is arena and as far as I'm aware, it scales so your weapon/gear doesn't really matter. The weapon upgrade system is cool but seems pointless if the only PVE is a few dungeons. You actually sit in a lobby while waiting for arena matches too.

TL;DR: It's more like an online street fighter where you have to level up before sitting in a lobby waiting for your 1v1 arena matches to start. If you like PVP and have good ping, it might be the perfect game for you but there's not really any other reasons to play it.